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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Coolant system holds pressure but not vaccume?

  • Thread starter Thread starter Floydian100
  • Start date Start date Jan 16, 2023
F

Floydian100

Member
Dec 17, 2022
13
1
13
Maryland
Jan 16, 2023
#1
  • Jan 16, 2023
  • #1
Replaced the intake on my 01 gt and boy what a pain in the ***. Tore it down 3 times to seal correctly as the Dorman is junk. Anyway, fixed all the leaks and pressure tested to 16 pounds and holds 10-15 minutes before I fill the system. When filling with the vac fill tool I have as I bought due to having serious issues getting air out I noticed it won’t hold Vaccume for long. Once I’m at 25 it will hit 20 within 5 minutes, why will the system hold pressure but not vaccume?

I also made sure the tool was tight with bubble spray.
 
S

Shuttleman83

Active Member
Jun 30, 2019
239
13
28
USA
Jan 22, 2023
#2
  • Jan 22, 2023
  • #2
Get a new 16 psi res cap.
 
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